Difference Between Union all and Union

Many People know answer for this , but some people are there who are new into this,

What is UNION?

UNION is used to join two related set of data.UNION will give a distinct result ie; it

will avoid duplicates.How ever  the UNION  is bit slower due to distinct sort.

UNION

What is UNION ALL

UNION ALL is also used to join two related set of data.UNION ALL will not Provide  a distinct sort.So it is very fast than UNION

UNION ALL